From a recipient's standpoint, there are few reasons Quora's emails stand out:

Quora sends weekly instead of daily emails. It's hard to keep up with a daily email. But a weekly email is much easier to manage and therefore less annoying to receive.

The subject line is always a catchy question. "Is a $100k salary too much for an angel/VC-backed startup co-founder?" for example.

The emails contain interesting, high quality, and personalized content. Algorithms pick the stories, not editors. It's a great content discovery experience.

It shows someone credible tied to every story featured. When you see someone who's lost a sister answering the question, "What it feels like to lose a sibling," it makes you more curious about the answer.

"Well, it is algorithmically created. I wanted to make something that people would read. What I didn’t want was something that was an annoying little email. It took awhile, but it has paid off. We had two people who worked on it (in a dedicated fashion) for a month, though we had been working on-and-off on it for nearly a year and a half. The email essentially looks at what people are reading and engaging (with) the most on Quora."